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Finding the Fourth Proportional to 656.20, 903.18 and 618.40

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Solution

The fourth proportional to 656.20, 903.18 and 618.40 is: 851.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.20 : 903.18 = 618.40 : x
  2. Step 2: Convert to fraction form
    656.20/903.18 = 618.40/x
  3. Step 3: Cross multiply
    656.20x = 903.18 × 618.40
  4. Step 4: Simplify right side
    656.20x = 558,526.51
  5. Step 5: Solve for x
    x = 558,526.51/656.20
  6. Step 6: Final answer
    x = 851.15

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.